The Table Mountain (Cusac) mine is located approximately 4 kilometres south of the main Erickson mine (MINFILE 104P 029). Previously, mining was done on the Dino and Hot vein systems, but the main ore zone is the Eileen vein system.
The Cusac veins are hosted by the Devonian to Triassic Sylvester Allochthon. The Sylvester Allochthon is a fault-bounded imbricate assemblage of regionally metamorphosed (greenschist facies) oceanic crust consisting of metavolcanics, metasediments and ultramafics. Potassium-argon dating of sericite from a quartz stringer associated with an auriferous quartz vein hosted by metavolcanics, indicate a Lower Cretaceous age.
In the mine area, the Mississippian to Upper Triassic Slide Mountain Complex assemblage consists of greenstones, argillite, serpentinite, listwanite and quartz veins. Two sets of steeply dipping quartz veins are known, one striking north and the other east. The veins occupy fault and fracture zones, mainly in footwall greenstones adjacent to a greenstone-argillite contact and vary in width from 0.75 to 3.0 metres. The north striking system has been traced for at least 750 metres.
The mineralization consists of galena, pyrite, sphalerite, chalcopyrite, tetrahedrite and gold. The hostrock adjacent to the quartz veins has been silicified and contains graphitic alteration, and the serpentinites have commonly been altered to listwanite. It has been noted that where quartz veins cut or lie directly beneath a listwanite body the gold values for that portion of the vein increase. Dussell (1986) proposes that "ore solution infiltrated and metasomatized bodies of partially serpentinized peridotite producing a listwanite. Gold precipitation was then triggered by a decrease in sulfur activity when the ore solution reacted with the listwanite parent". Pyrite occurs as coarse-grained and fine-grained knots throughout but increases in abundance towards the wallrock contact. Sphalerite, tetrahedrite and minor galena occur within the pyrite knots and normally indicate better gold grades.
Exploration work in the late 1970s and early 1980s is reported to have identified numerous veins and/or veined zones on the former Cordoba claim including the Dino (Fred), Flat, Hot, East-West, Cominco, Prosser and Jennie veins.
The Dino (Fred) quartz vein is located immediately east of the former mill pond and averages approximately 0.75 metre in width at surface but can vary up to 4.5 metres wide. The vein strikes 160 degrees with a dip of 55 to 85 degrees west. Mineralization is comprised of tetrahedrite, pyrite and visible gold. The vein has been exposed for approximately 45 metres along strike. A historical adit was collared on the west extension of the vein.
The Flat and Hot veins are located quartz vein is up to 1.5 metres thick and approximately flat-lying along the contact between carbonaceous slate and a chert and/or metavolcanic and an argillite. The vein has been traced discontinuously for 40 metres along an east-west trend. Mineralization comprises minor pyrite, galena, chalcopyrite and rare visible gold. Gold grades in the vein are reported to increase towards its junction with the steeper dipping Hot (no. 5) and 6 veins. The Hot vein is exposed for approximately 24 metres along strike and varies from 0.6 to 1.5 metres in width. The vein strikes 070 degrees and dips 50 to 70 degrees north. The vein is hosted in carbonate-altered metavolcanics immediately below the contact with an overlying graphitic argillite.
The Cominco vein is located approximately 350 metres west of the Hot vein and varies from 0.5 to 1.5 metres in thickness along a 10-metre strike length. The vein strikes northeast with a steep dip in carbonate-altered metavolcanics.
The Prosser vein strikes east-west and varies in thickness up to 1.0 metre in carbonate-altered metavolcanics associated with quartz-carbonate-fuchsite (listwanite) alteration and numerous other smaller veins, ranging up to 0.5 metres in width. The vein hosts generally minor fine-grained pyrite with local chalcopyrite, galena and rare visible gold.
In 1979, a 226.8-kilogram bulk sample from the Dino vein is reported to have averaged 112.5 grams per tonne gold, whereas four samples (17458 through 17461) from the vein yielded from 29.4 to 2520 grams per tonne gold (Assessment Report 8634). In 1981, a further 531 tonnes of ore from an open pit on the Dino vein processed at the Erickson mill.
The Eileen vein was discovered in 1985 and production commenced in 1986; by 1988, the vein had been mined over a strike length of 300 metres and downdip for approximately 30 metres. The Michelle vein, approximately 30 metres from the Eileen, was also discovered in 1985 by underground mapping and drilling and has had limited work done on it (A. Boronowski, personal communication, November 1988). The Jill vein was also discovered at this time.
In 1990, the Heather and Bain veins were discovered on the property. The Bain vein is a well-mineralized, steeply dipping east-west structure. A 39-metre section of the vein assayed in the range of 51.4 to 68.5 grams per tonne gold uncut over 1.2 to 1.8 metre widths indicated by surface trenching and drilling (George Cross News Letter No.35, 1990). The Bain vein is 457 metres south of the Eileen vein system.
Past production at Table Mountain (Cusac) is included as part of the Erickson mine (MINFILE 104P 029).
A historical adit (Cusac), numerous trenches, and drillcores have been identified on the occurrence area and likely date to the late the late 1930s and/or early 1940s.
During the 1979 field season, Cusac Industries Ltd. conducted an exploration program on a five-unit area of their Cordoba and Pete claims; a VLF-EM survey on both areas was also carried out. The 1979 exploration program included geological mapping, rock sampling, trenching and eight diamond drill holes, totalling approximately 600 metres.
In 1982, Cusac Industries Ltd., completed a program of underground development including a crosscut, 90 metres of drifting and a raise to the surface of the Hot vein. In 1984, Erickson Gold Mining Corp. optioned the property and completed a program of geological mapping, trenching and percussion drilling on the Cordoba and Pete claims. Exploration work in 1985 included trenching and 77 diamond drill holes, primarily on the Eileen vein with lesser amounts of drilling on the Prosser, Cominco, Dino and Pete veins. In 1986, Erickson Gold Mining completed 40 diamond drill holes, totalling 4385.3 metres, on the Eileen, East-West, Dino, Hot-Flat, Jill and Sky veins. A program of underground drilling was completed in 1987. In 1988 and 1989, surface programs of geological mapping, trenching, rock sampling, diamond drilling and geophysical surveys were completed.
In 1990 and 1991, Erickson Gold Mining completed a program of trenching, 56 diamond drill holes, totalling 9822.0 metres, and a 48.0 line-kilometre induced polarization on the Nu-Tara property. In 1993, a further drilling program of 17 diamond drill holes, totalling 1522.5 metres, was completed on the Bain vein and related zones of mineralization. During 1994 through early 1995, 28 diamond drill holes, totalling 734.4 metres, were completed on the property.
Current reserves, as of 1994, at the East Bain were reported at 21,770 tonnes grading 17.1 grams per tonne gold; unclassified reserves at the Michelle were 22,677 tonnes grading 27.4 grams per tonne gold; current reserves at the Bonanza were 4535 tonnes grading 17.1 grams per tonne gold; current reserves at the West Bain were 31,748 tonnes grading 34.28 grams per tonne gold; unclassified reserves of three surface pits were 9071 tonnes grading 10.2 grams per tonne gold (George Cross News Letter No.90 [May 11], 1994; P. Wojdak, personal communication, 1995).
Cusac Gold Mines Ltd. produced 489 kilograms of gold in 1994 from approximately 31,075 tonnes of ore, milled intermittently at a daily throughput of 275 tonnes. During 1995, Cusac completed a decline to the Michelle high-grade zone and continued to develop the zone, producing approximately 45 tonnes of development ore per day for blending with the lower-grade Bain vein material.
As a result of encouraging drilling results in the Michelle high-grade zone, Cusac is proceeding with completion of the 10 portal, a major underground development project, to improve access to the orebody and, ultimately, increase production. Cusac will advance the partially constructed adit (1570 metres) approximately 915 metres to the target area, with planned completion in the spring of 1996. Meanwhile, mining, development and exploration will continue through the existing decline. The mill is currently processing high-grade material from both the Michelle high-grade zone and the Catherine vein (MINFILE 104P 113) open pit. The mill has been winterized and is expected to continue operating through most of the winter. Milling resumed in September 1995 and gold production, from intermittent daily throughput of 150 tonnes to the end of October, is approximately 300 kilograms (Information Circular 1996-1, page 8).
In 1995, with Explore BC program support, Cusac Industries Ltd. completed 2802.3 metres of underground diamond drilling in 31 holes on the Michelle vein. This work proved that the Michelle vein is high-grade but also complexly faulted. The drilling also discovered a second high-grade ore shoot, the Lily vein, subparallel to Michelle. A drill-indicated reserve of 10,000 tonnes grading 96.3 grams per tonne gold has been outlined in the Lily vein, which has greater down-plunge and strike extension potential than Michelle (Explore BC Program 95/96 - A143).
The mine, had, to the end of August 1996, produced 489,047 grams gold. Total reserves at Table Mountain (including the Vollaug vein) are 131,120 tonnes grading 12.69 grams per tonne gold (Northern Miner - October 14, 1996). The published reserve in 1997 is 139,635 tonnes grading 10.29 grams per tonne gold (Northern Miner - April 7, 1997).
Also in 1996 and 1997, Cusac Gold Mines completed programs of geological mapping, trenching, rock sampling and 29 diamond drill holes, totalling 3867.7 metres, on the Bear vein (Sun claim).
Underground mining in the Michelle high-grade zone (including Lily vein extension) was suspended in June 1997. Mining has taken place over an 800-metre strike. Opencut mining of the Vollaug vein was expected to end in August 1997 and the mill will shut down shortly thereafter.
The company estimated current proven and probable reserves at 72,568 tonnes grading 17.1 grams per tonne gold (T. Schroeter, personal communication, 1997).
In 1998, Cusac mined the Bear vein (MINFILE 104P 029) and produced 28,522 grams of gold from 1800 tonnes.
In 2002, Cusac Gold Mines Ltd. completed a 1022-metre drill program on the eastern part of the Bain vein (Press Release - Cusac Gold Mines Ltd., September 20, 2002). In 2003, Cusac Gold Mines Ltd, completed two diamond drill holes, totalling 626 metres, on the Gap zone. The mine had been on care and maintenance status since 1999. In 2002, drilling defined a resource of 22,000 tonnes grading 33.78 grams per tonne gold on the east extension of the Bain vein (Mineral Exploration Review 2003, page 16).
In 2004, exploration drilling (6478 metres in 41 holes) resulted in discovery of a new vein by Cusac Gold Mines Ltd. The Rory vein trends 020 degrees and dips steeply to the west. It was found north of the Jennie and Bear veins in a prospective but relatively unexplored portion of the property. The Rory vein averages 3 metres in true width over a length of 130 metres and dip extent of 45 metres, and is 25 metres above a main haulage drift. The Rory vein contains an indicated mineral resource of 19,958 tonnes at 12.17 grams per tonne and an inferred mineral resource of 1899 tonnes at 11.31 grams per tonne gold (Press Release - Cusac Gold Mines Ltd., November 22, 2004). The Rory and East Bain veins contain a combined total indicated resource of 40,059 tonnes at 16.9 grams per tonne gold) and a total inferred mineral resource of 3056 tonnes at 33.00 grams per tonne gold (Press Release - Cusac Gold Mines Ltd., November 22, 2004). National Instrument 43-101 compliancy was not reported.
In 2006, Cusac Gold Mines Ltd. rehabilitated the underground workings and restarted mining operations and mill/facilities rehabilitation in mid-August. The company expects its first gold pour in mid-November; work is on the East Bain and Rory veins. Resources reported by the company are a combined probable mineral reserve of 39,916 tonnes grading 15.24 grams per tonne. Also reported are inferred mineral resources of 3056 tonne grading 29.86 grams per tonne for the East Bain vein alone. The initial focus was on the Rory vein with minor production, but then shifted to the Bain vein where a probable reserve of 25,000 tonnes grading 17 grams per tonne gold has been identified. The company completed considerable underground work, including advancing a decline to 150 metres from the East Bain vein when it intersected highwater flow that halted mining on October 1, 2007 (Information Circular 2008-1, page 6).
Winterization of the Table Mountain Gold Mine was successfully completed to ensure a smooth resumption of development and mining activities in the spring of 2008. At that time, management has determined that larger scale pumping equipment and other measures will enable the company to handle the volumes of water encountered in the East Bain decline earlier this year. A number of small quartz veins were intersected in the East Bain decline containing visible gold. Assays from these veins confirm the visual observations, with grades of 53.5 grams per tonne gold over 0.2 metre and 48.7 grams per tonne gold over 0.2 metre in two of these quartz stringers. Although the veins are not of minable width, they are a good indicator of pathways for gold-bearing fluids and they may lead to possible new vein systems in the area.
In 2007 and 2008, Hawthorne Gold Corporation and Cusac Gold Mines Ltd. entered into a merger agreement whereby the two companies would continue to operate under the corporate entity of Hawthorne Gold Corporation. Hawthorne became the owner and operator of Cusac’s Table Mountain and Taurus (MINFILE 104P 012) properties and proceeded to form a private subsidiary company, Cassiar Gold Corporation, to retain assets acquired from Cusac. The entirety of this land package became known as the Cassiar Gold property. Table Mountain project areas contain the historical Erickson Gold Mines mine site (MINFILE 104P 029) located adjacent to the southern shores of McDame Lake, historical underground workings at the Main Mine area along Erickson Creek, historical portals used to mine and access the Vollaug vein (MINFILE 104P 019) on top of Table Mountain and east of the Main Mine, and the Cusac and Bain portals approximately 8 kilometres south of the Main Mine. The Taurus project area is approximately 6 kilometres north of the Main Mine and contain the historical Taurus, Sable and Plaza portals and underground workings. The intent of the 2008 exploration year was to reassess the overall scope of the Cassiar Gold property. The exploration program comprised field reconnaissance, soil sampling (606 samples), rock and chip sampling (365 samples), airborne magnetic and VLF-EM surveying (6567 kilometres), geophysics ground truthing and diamond drilling (15 holes totalling 2536.5 metres on the East Bain vein, MINFILE 104P 070). A grab sample (5000001) of the East-West vein assayed 22.9 grams per tonne gold (Assessment Report 30623).
During 2007 through 2010, Hawthorne Gold Corp. consolidated the Cassiar Gold Project by acquiring 46 mineral claims from American Bonanza Gold Corp., 46 mineral claims from Cusac Gold Mines and 124 mineral claims by staking or other mineral claim purchases. In 2009, underground development extended the Bain decline by 200 metres to the east and towards the East Bain vein. Also at this time, a program of geochemical sampling, trenching and 41 diamond drill holes, totalling 7538.7 metres, was completed.
In 2010, Cassiar Gold Corp., a wholly owned subsidiary of China Minerals Mining Corporation, completed a helicopter-borne time domain-electromagnetic, magnetic and radiometric survey covering 5090 line-kilometres. On April 5, 2011, Hawthorne was renamed China Minerals Mining Corporation. Also, during this time, the property went under care and maintenance and a particulate gold recovery program was conducted to extract gold from the mill. Underground rehabilitation took place in the Cusac portal.
In 2012, China Minerals Mining Corporation completed drilling campaigns at the Taurus (MINFILE 104P 012; 43 holes) and Table Mountain (10 holes) properties of their Cassiar Gold project. The 10 holes, totalling 1355 metres, from the Table Mountain area were completed on the Sky (MINFILE 104P 078) vein. In 2013, China Minerals Mining Corp. completed a small program of prospecting and geochemical (stream, rock and soil) sampling on the Hunter and Pooley areas.
In 2018, Cassiar Gold Corp. completed a program of sampling, metallurgical studies and 128 direct push drillholes, totalling 512.0 metres, on the mines tailings to examine the potential for gold recovery in a tailings reprocessing program. Tailings samples yielded from 0.51 to 6.67 grams per tonne gold with an average of 1.26 grams per tonne gold (Assessment Report 38310).
In 2019, Margaux Resources completed a program of prospecting, geological mapping and rock sampling on the area as the Cassiar Gold property.
In 2020, Cassiar Gold Corp. completed a program of regional photogeological interpretation, prospecting and rock sampling on the Cassiar Gold property.